1. Field of the Invention
This invention pertains to an apparatus and a method for dispensing cold post-mixed beverage using compressed gas for pneumatic power of the dispenser.
2. The Prior Art
The accepted procedure and structure for dispensing post-mix beverages utilizes stainless steel syrup tanks. The tanks are filled at a bottling or distribution center, pressurized, and then transported to a place of use. The tanks always remain pressurized and are connected to a carbon dioxide bottle and kept pressurized during dispensing. The tank size must be of about five gallons in order to be economically viable or the container cost per unit of volume becomes excessive. However, this five-gallon tank is quite heavy and its use is restricted to commercial distribution channels such as restaurants and bars. A continually pressurized tank also requires an educated and knowledgable user who can connect and disconnect the pressurized tanks without leakage. The pressurized tank must be returned after usage, for cleaning and refill for its next trip, and therefore two-way transportation over predetermined routes is a business necessity. The usage of pressurized tanks does not lend itself to domestic beverage dispensers, the domestic distribution channels or to use by unskilled people.
An alternative to the usage of pressurized tanks is usage of a package called the bag-in-box (BIB). The BIB is a plastic bag inside of a cardboard box. The bag is not pressurized and beverage is drawn out of the bag by a suction pump which may be electrical or gas powered. The BIB has enjoyed limited success for soft drink syrups. There have been many problems including pump failure, leakage, pump burn-out, seal failure, and bag leakage. The BIB has enjoyed greater success as a retail package for wines, where there has been no need to use a pump. The BIB has been of 2-5 gallons in order to be an economically viable package. Smaller package sizes such as the sizes typically retailed, are not economically effective. Fluid connection to a BIB has been troublesome and leakage is all too frequent.
Attempts have been made to devise a compressed gas powered beverage dispenser that does not require electricity for power of beverage pumps. There have been some technical successes but there examples are extremely complicated, failure-prone, and costly. These devices have not been successful in the marketplace even when embodied as relatively expensive vending machines. These machines have been very difficult to keep clean, very difficult to sanitize, and very difficult to repair. The prior art also has never been able to integrate the beverage pump and tanks into a goof-proof and leak-proof package.